8 lifestyle changes to make if you want to get rich in 2019

As self-made millionaire and author Steve Siebold writes in "How Rich People Think," he has benefited from a life-changing realization:  "To get rich, I had to learn to think like a rich person. Once I changed my thinking, the money started to flow."

And, he notes, "the only way to learn how to think like a rich person is to study them."

Here are eight lifestyle changes that have helped Siebold and other self-made millionaires build wealth. If you're looking to change your life in 2019, they could work for you.

The richest people focus on earning, and typically they aren't content with one source of revenue.

As author Thomas C. Corley found in his multi-year study of self-made millionaires, the rich "do not rely on one singular source of income," he writes in "Change Your Habits, Change Your Life." In fact, "65 percent had at least three streams of income that they created prior to making their first million dollars," Corley says, such as real-estate rentals, a side hustle or a part-time job.

Your community matters. It can even affect your net worth, says Siebold: "In most cases, your net worth mirrors the level of your closest friends. … We become like the people we associate with, and that's why winners are attracted to winners."

Coreley agrees: "Wealthy, successful people are very particular about who they associate with," he writes. "Their goal is to develop relationships with other success-minded individuals." If you don't know have highly motivated people in your network, Corley suggests joining a professional group.

"Investing money is how you will get super rich, " says self-made millionaire Grant Cardone. "The only reason to save money is to one day invest money."

In fact, how much you save and invest is often more important than the size of your paycheck. Personal finance expert Ramit Sethi writes in "I Will Teach You to Be Rich " that, "on average, millionaires invest 20 percent of their household income each year. Their wealth isn't measured by the amount they make each year, but by how they've saved and invested over time."

Once you've committed to investing your money, the easiest way to stick with it over time is to make the process automatic — meaning that you have money from your paycheck or checking account sent to your investment accounts every month, before you even see it.

Simply putting your finances on autopilot could free up an extra $700 a month, or $8,400 a year, for the rest of your life.

If you want to earn more or get ahead in life, you have to be willing to step outside of your comfort zone.

This includes negotiating your salary. It's one of the simplest ways to boost your earning potential, since those who ask for more usually get it. Yet most people don't even try.

Sure, negotiation can be a tricky business, but not getting paid what you're worth could mean the difference between an average life and a rich one. After all, as self-made millionaire Grant Sabatier says, "The number one thing that will dictate your future earning potential and get you to $1 million the fastest is how much money you are being paid today."

Wealthy people share one important trait: They are dedicated to self-improvement, Corley has found.

Reading a book about an unfamiliar topic, taking a class or joining a local networking group are great ways to develop a new skill. In fact, learning a new skill could help you land a job, one former Google career coach says.

"When you do things that are outside your comfort zone and outside that circle, it causes discomfort," Corley writes. "But each time you engage in a new activity that causes discomfort, you expand your circle; you grow as an individual."

"I didn't buy my first luxury watch or car until my businesses and investments were producing multiple secure flows of income," writes Cardone, who was struggling to make ends meet not long before hitting seven figures. "I was still driving a Toyota Camry when I had become a millionaire. Be known for your work ethic, not the trinkets that you buy."

Warren Buffett seems to live by a similar philosophy. After all, the legendary investor eats at McDonald's and never spends more than $3.17 on a breakfast sandwich.

If you set your expectations exceptionally high and are up for any challenge, you're on the right track. After all, "no one would ever strike it rich and live their dreams without huge expectations," Siebold writes.

Don't miss: 8 simple money habits that will help you earn more in 2019

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